Senior Member
Last Online: 2 Days Ago 07:02 PM
Join Date: Dec 2007
Location: Stormking Mountain
Age: 21
Posts: 1,249
Cash Credits: 19,360
|
I think the following should be put into the book. This was originally written by ghost.
So, congratulations. You've just finished milling and screening some Blackpowder, or you've got a bit of Methyl ethyl ketone peroxide on a filter paper. Now what?
Well, you're gonna blow it up, obviously, but how will you do that?
You need to choose your firing mechanism based on what the situation for the shot is. Personally, I use e-det in damn near everything, partially because cannonfuse is impossible to get in Aus, but also because it's much mroe reliable. We'll start at the top.
SPARKLERS
Sparklers are not safe. They throw hot burning fragments everywhere, greatly increasing the risk of premature detonation. Luckily, they have a predictable burn rate, guaranteed ignition, and are very, very cheap. In order to use a sparkler as a fuse for (generally, a thermite charge, black or flash powder - Don't trust high explosives to something this unsafe!) your munition, decide how far you want to bury it into your explosive. Generally, about an inch, to two inches is acceptable, and very reliable. Wrap the rest of the length in a few layers of alfoil, to catch the white-hot sparking fragments, leaving only the darker-coloured primer tip open.
SAFETY FUSE
Brilliant stuff. Cheap, reliable, and comes in dozen-metre rolls. Commonly used in nearly every commercial firecracker. Simple to use - Plug it into your powder, ignite, and, well, sit back and watch the fireworks. Often available waterproofed, to light submerged charges. The downside is that it's not readily available in several countries. Common brands/synonyms are Visco, Cannonfuse, etc.
You may have also heard of 'flying fish' or 'falling leaf' visco, this is NOT to be used for traditional fusing. They are a special, coloured, sparkling fuse which is chopped into pieces a few inches long and packed into your star, to give a crazy, slow-burning coloured falling trail effect when blown.
A related fuse is Thermalite - Real old-school stuff, you need to strip the fuse for however much you want to burn, if unstripped it burns slowly, and the various different kinds of fuse burn at different stripped rates. Usually fired by e-match or flashbulb.
BLACKMATCH
Blackmatch is several cotton threads twined together, moistened, and rubbed with black powder then left to air-dry. It burns quickly and unreliably because of the non-intimate nature and shonky preperation, and should not be relied upon to safely ignite charges, or for any kind of timing.
QUICKMATCH/PIPEMATCH
A quick match or piped match is a type of black powder fuse that burns very quickly, some hundreds of feet per second. They consist of black matches covered with a loose paper wrap (pipe). When lit, the flame propagates quickly down the paper pipe from the hot gases produced by the burning powder. Quick matches are used in professional fireworks displays to pass fire nearly instantly between devices that must be physically separated while firing simultaneously, such as a finale rack. Devices which should fire in sequence can be branched from a single master fuse, consisting of quick match spliced onto Visco fuses of various length for time delays. The easiest way to produce it is to lay a length of masking tape, sticky-side up, and carefully pour black powder down the middle, then fold over on itself and twist. The final product is fragile, so don't handle roughly or your shells might not fire at all. The tape method is better referred to as stickymatch.
SLOWMATCH
A slow match is a very slow-burning fuse consisting of a hemp or cotton rope saturated with an oxidizer such as potassium nitrate. Slow matches are used as a source of fire for manually lighting other devices, such as matchlock guns, or fuses on black powder cannons. Before percussion caps, slow matches were most suitable for use around black powder weapons because it could be roughly handled without going out, and only presented a small glowing tip instead of a large flame that risked igniting powder supplies nearby. Today's punks (wood splints covered with ground plant pith saturated with nitrate) used for lighting consumer fireworks are a type of slow match.
ISFE/E-MATCH
An Igniter Safety Fuse Electric (ISFE) lights a main fuse or device when activated by an electrical current. They typically consist of a pair of wires leading to a thin resistance wire that heats when current is applied. The resistance wire is covered by a dot of first fire that ignites from the wire heating, providing enough fire to reliably ignite the main fuse via a mechanical connection, or the device directly. Estes model rocket motors are lit by a type of electric match. Large fireworks displays are launched with complex timing sequences using a computer that energizes electric matches connected to the individual device fuses.
STANDFUSE/SPOOLETTE
A spoolette is a delay fuse consisting of a hollow wooden dowel rammed full of black powder. A spoolette is glued into the wall of a fireworks shell and ignited by the lift charge that launches the shell into the air. The spoolette, after a delay that allows the shell to reach its top of trajectory, ignites the shell's main effect(s). The tough wood construction ensures that the fuse burns reliably despite the explosive force and acceleration of the launch.
I'll take some pics of the various types today, and when I get back from going for a smoke and a jog I'll talk about HE det methods.
|